The first symptom is usually a change in personality or behaviour (which is out of character for the person) – the symptoms may come on very slowly and not be noticed as definitely abnormal at first. The symptoms include the following:
In the early stages memory is often well maintained on psychological testing (unlike in Alzheimer’s disease) but difficulties in organisation and concentration often lead to an apparent memory problem in daily life and so this is also a common complaint.
Behaviour and aspects of thinking (cognitive functions) will be assessed, initially by a doctor, and often followed by a more detailed assessment by a psychologist. Brain scans can show the loss of brain cells in FTD (shrinkage of the affected parts of the brain) but there is no single test that can specifically diagnose FTD with complete reliability during a person’s lifetime. Furthermore, in the early stages of the disease the scan may look normal. Diagnosis is therefore largely based on clinical judgment and FTD can be confused with other disorders in which there are problems with behaviour (e.g. some psychiatric disorders) and with other dementias. The doctor will often arrange blood tests or other tests (usually including detailed brain scans, in particular MRI, and sometimes a lumbar puncture or other specialised tests) to help confirm the clinical diagnosis and rule out diseases that can produce similar symptoms to FTD.